Audio is out of sync

Anything and everything to do with DCP-o-matic.
Post Reply
EdwardS
Posts: 3
Joined: Wed Feb 21, 2018 2:29 pm

Audio is out of sync

Post by EdwardS »

On playback at a screening our DCPOM - audio was slightly off. Most notable in sound effects coming late. The Mp4 file was not out of sync. Any suggestions for novice user?
Thank you.
(90 minute film)
Carsten
Posts: 2648
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Audio is out of sync

Post by Carsten »

Hmmm... is this stereo audio? Technically, in a stereo composition, there is no way how individual elements like fx sounds could have individual delays, so I assume that the sync issue was just more appearent with these sounds than with other audio.

I guess you have no delay configured in DCP-o-matic?

Maybe you could sent the project metadata file to Carl (or upload as attachment in this thread)?

Is it possible you used a J2K compression rate above 250Mbit/s? What's the frame rate of the source file?

I assume the audio is included in the source MP4?

- Carsten
EdwardS
Posts: 3
Joined: Wed Feb 21, 2018 2:29 pm

Re: Audio is out of sync

Post by EdwardS »

Thank you. It was an MP4 29.9fps Stereo

I only have basic skills/computer literacy...I try to follow the basic instructions and then close my eyes and hit the button.


The Mp4 was not out of sync.
The DCP wasn't so bad that it was unwatchable but I wouldn't want to screen it again as is.
EdwardS
Posts: 3
Joined: Wed Feb 21, 2018 2:29 pm

Re: Audio is out of sync

Post by EdwardS »

<?xml version="1.0"?>

-<Metadata>

<Version>36</Version>

<Name>DCP KARAOKE KNIGHTS</Name>

<UseISDCFName>1</UseISDCFName>

<DCPContentType>FTR</DCPContentType>

<Container>185</Container>

<Resolution>2K</Resolution>

<J2KBandwidth>100000000</J2KBandwidth>


-<ISDCFMetadata>

<ContentVersion>1</ContentVersion>

<AudioLanguage/>

<SubtitleLanguage/>

<Territory/>

<Rating/>

<Studio/>

<Facility/>

<TempVersion>0</TempVersion>

<PreRelease>0</PreRelease>

<RedBand>0</RedBand>

<Chain/>

<TwoDVersionOfThreeD>0</TwoDVersionOfThreeD>

<MasteredLuminance/>

</ISDCFMetadata>

<VideoFrameRate>30</VideoFrameRate>

<ISDCFDate>20180222</ISDCFDate>

<AudioChannels>6</AudioChannels>

<ThreeD>0</ThreeD>

<Sequence>1</Sequence>

<Interop>0</Interop>

<Signed>1</Signed>

<Encrypted>0</Encrypted>

<Key>137cb582b8d415b58ef8fb6ea79a7b62</Key>

<ContextID>e81094af-29a9-4445-b60a-0b01b393a197</ContextID>

<ReelType>0</ReelType>

<ReelLength>2000000000</ReelLength>

<UploadAfterMakeDCP>0</UploadAfterMakeDCP>


-<Playlist>


-<Content>

<Type>FFmpeg</Type>

<Path>C:\Users\tRAVIS\Documents\Movie Studio 14.0 Platinum Projects\2 19 2018 FINAL CUT IN MP4 FOR DCP\Renders\2 20 2018 DCP CUT IN MP4.mp4</Path>

<Digest>1e416564d5e29e4ad91d01aa05c3fc209571869767</Digest>

<Position>0</Position>

<TrimStart>0</TrimStart>

<TrimEnd>0</TrimEnd>

<VideoFrameRate>29.97002997002997</VideoFrameRate>

<VideoLength>163996</VideoLength>

<VideoWidth>1920</VideoWidth>

<VideoHeight>1080</VideoHeight>

<VideoFrameType>2d</VideoFrameType>

<SampleAspectRatio>1</SampleAspectRatio>

<LeftCrop>0</LeftCrop>

<RightCrop>0</RightCrop>

<TopCrop>0</TopCrop>

<BottomCrop>0</BottomCrop>


-<Scale>

<Ratio>235</Ratio>

</Scale>


-<ColourConversion>


-<InputTransferFunction>

<Type>Gamma</Type>

<Gamma>2.2</Gamma>

</InputTransferFunction>

<YUVToRGB>1</YUVToRGB>

<RedX>0.64</RedX>

<RedY>0.33</RedY>

<GreenX>0.3</GreenX>

<GreenY>0.6</GreenY>

<BlueX>0.15</BlueX>

<BlueY>0.06</BlueY>

<WhiteX>0.3127</WhiteX>

<WhiteY>0.329</WhiteY>

<OutputGamma>2.6</OutputGamma>

</ColourConversion>

<YUV>1</YUV>

<FadeIn>0</FadeIn>

<FadeOut>0</FadeOut>

<AudioGain>-10</AudioGain>

<AudioDelay>0</AudioDelay>


-<AudioStream>

<Name>eng</Name>

<Id>1</Id>

<FrameRate>48000</FrameRate>

<Length>262655993</Length>


-<Mapping>

<InputChannels>2</InputChannels>

<OutputChannels>16</OutputChannels>

<Gain Output="0" Input="0">1</Gain>

<Gain Output="1" Input="0">0</Gain>

<Gain Output="2" Input="0">0</Gain>

<Gain Output="3" Input="0">0</Gain>

<Gain Output="4" Input="0">0</Gain>

<Gain Output="5" Input="0">0</Gain>

<Gain Output="6" Input="0">0</Gain>

<Gain Output="7" Input="0">0</Gain>

<Gain Output="8" Input="0">0</Gain>

<Gain Output="9" Input="0">0</Gain>

<Gain Output="10" Input="0">0</Gain>

<Gain Output="11" Input="0">0</Gain>

<Gain Output="12" Input="0">0</Gain>

<Gain Output="13" Input="0">0</Gain>

<Gain Output="14" Input="0">0</Gain>

<Gain Output="15" Input="0">0</Gain>

<Gain Output="0" Input="1">0</Gain>

<Gain Output="1" Input="1">1</Gain>

<Gain Output="2" Input="1">0</Gain>

<Gain Output="3" Input="1">0</Gain>

<Gain Output="4" Input="1">0</Gain>

<Gain Output="5" Input="1">0</Gain>

<Gain Output="6" Input="1">0</Gain>

<Gain Output="7" Input="1">0</Gain>

<Gain Output="8" Input="1">0</Gain>

<Gain Output="9" Input="1">0</Gain>

<Gain Output="10" Input="1">0</Gain>

<Gain Output="11" Input="1">0</Gain>

<Gain Output="12" Input="1">0</Gain>

<Gain Output="13" Input="1">0</Gain>

<Gain Output="14" Input="1">0</Gain>

<Gain Output="15" Input="1">0</Gain>

</Mapping>

<FirstAudio>0</FirstAudio>

<CodecName>aac</CodecName>

</AudioStream>

<FirstVideo>3203</FirstVideo>

<ColorRange>1</ColorRange>

<ColorPrimaries>2</ColorPrimaries>

<ColorTransferCharacteristic>2</ColorTransferCharacteristic>

<Colorspace>2</Colorspace>

<BitsPerPixel>12</BitsPerPixel>

</Content>

</Playlist>

</Metadata>
Carsten
Posts: 2648
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Audio is out of sync

Post by Carsten »

Your video is 29,97 fps, and the DCP created from that 30fps. This COULD be the reason for it. For a simple DCP with just a single content file it is hard to say why this happened, it is not common to have that issue. I have seen misaligned cinema audio systems, though, and that system could have an issue with 30fps DCPs as well.

Are you in a situation to play test files on that system? There are sync-test DCPs that can be used to pinpoint possible issues.

- Carsten
carl
Site Admin
Posts: 2338
Joined: Thu Nov 14, 2013 2:53 pm

Re: Audio is out of sync

Post by carl »

Is it feasible to get hold of the mp4 somehow? Or a clip of it (starting from the beginning)?
Post Reply